1992 Mercury Tracer Diesels, Won't Start

I have a 1992 Mercury Tracer with a 1.9 L engine with 117000 miles on it. The engine will not fully start up and when you turn the key off the car still tries to run (diesels), Thinking that the car had jumped time, I decided to replaced the timming belt. When I checked the timming marks all were lined up as they should be, having the car apart I went ahead and replaced the belt any way. Marks were still lined up as they should be. Still the car diesels and will not fully start. Checked the ignition module and replaced it because the original showed that it did not pass the test. Put the new module in and the car still diesels and will not start up or run. Spark plugs and wires and fuel filter have been replaces. Oxyger sensor has been replaced, all this has been done in the last 4 weeks. I am at my witts end and the repair manual keeps saying timeing could it be the timing sensor gone bad? I give up, help.